501(c)3

A 501(c)(3) or 501c3 organization is the most common type of the 29 types of 501(c) nonprofit organization in the United States. Most charitable non-profits in the United States that Americans commonly know of, and often make donations to, are 501(c)(3) organizations, ranging from charitable foundations to universities and churches. These organizations must be approved by the Internal Revenue Service to be tax-exempt under the terms of section 501(c)(3) of the Internal Revenue Code.

501(c)(3) tax-exemptions apply to entities that are organized and operated exclusively for religious, charitable, scientific, literary, or educational purposes, or for testing for public safety, or to foster national or international amateur sports competition, or for the prevention of cruelty to children or animals. 501(c)(3) exemption applies also for any non-incorporated community chest, fund, cooperating association or foundation that is organized and operated exclusively for those purposes. There are also supporting organizations—often referred to in shorthand form as "Friends of" organizations.

26 U.S.C. § 170, provides a deduction, for federal income tax purposes, for some donors who make charitable contributions to most types of 501(c)(3) organizations, among others. Regulations specify which such deductions must be verifiable to be allowed (e.g., receipts for donations over $250). Due to the tax deductions associated with donations, loss of 501(c)(3) status can be highly challenging to a charity's continued operation, as many foundations and corporate matching programs do not grant funds to a charity without such status, and individual donors often do not donate to such a charity due to the unavailability of the deduction.

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